1. Index
    1. Elements
    2. Element content categories
    3. Attributes
    4. Element interfaces
    5. All interfaces
    6. Events
    7. HTTP headers
    8. MIME types

Index

The following sections only cover conforming elements and features.

Elements

This section is non-normative.

List of elements
Element Description Categories Parents† Children Attributes Interface
aHyperlinkflow; phrasing*; interactive; palpablephrasingtransparent*globals; href; target; download; ping; rel; hreflang; type; referrerpolicyHTMLAnchorElement
abbrAbbreviationflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
addressContact information for a page or article elementflow; palpableflowflow*globalsHTMLElement
areaHyperlink or dead area on an image mapflow; phrasingphrasing*emptyglobals; alt; coords; shape; href; target; download; ping; rel; referrerpolicyHTMLAreaElement
articleSelf-contained syndicatable or reusable compositionflow; sectioning; palpableflowflowglobalsHTMLElement
asideSidebar for tangentially related contentflow; sectioning; palpableflowflowglobalsHTMLElement
audioAudio playerflow; phrasing; embedded; interactive; palpable*phrasingsource*; track*; transparent*globals; src; crossorigin; preload; autoplay; loop; muted; controlsHTMLAudioElement
bKeywordsflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
baseBase URL and default target navigable for hyperlinks and formsmetadataheademptyglobals; href; targetHTMLBaseElement
bdiText directionality isolationflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
bdoText directionality formattingflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
blockquoteA section quoted from another sourceflow; palpableflowflowglobals; citeHTMLQuoteElement
bodyDocument bodynonehtmlflowglobals; onafterprint; onbeforeprint; onbeforeunload; onhashchange; onlanguagechange; onmessage; onmessageerror; onoffline; ononline; onpageswap; onpagehide; onpagereveal; onpageshow; onpopstate; onrejectionhandled; onstorage; onunhandledrejection; onunloadHTMLBodyElement
brLine break, e.g. in poem or postal addressflow; phrasingphrasingemptyglobalsHTMLBRElement
buttonButton controlflow; phrasing; interactive; listed; labelable; submittable; form-associated; palpablephrasingphrasing*globals; disabled; form; formaction; formenctype; formmethod; formnovalidate; formtarget; name; popovertarget; popovertargetaction; type; valueHTMLButtonElement
canvasScriptable bitmap canvasflow; phrasing; embedded; palpablephrasingtransparentglobals; width; heightHTMLCanvasElement
captionTable captionnonetableflow*globalsHTMLTableCaptionElement
citeTitle of a workflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
codeComputer codeflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
colTable columnnonecolgroupemptyglobals; spanHTMLTableColElement
colgroupGroup of columns in a tablenonetablecol*; template*globals; spanHTMLTableColElement
dataMachine-readable equivalentflow; phrasing; palpablephrasingphrasingglobals; valueHTMLDataElement
datalistContainer for options for combo box controlflow; phrasingphrasingphrasing*; option*; script-supporting elements*globalsHTMLDataListElement
ddContent for corresponding dt element(s)nonedl; div*flowglobalsHTMLElement
delA removal from the documentflow; phrasing*; palpablephrasingtransparentglobals; cite; datetimeHTMLModElement
detailsDisclosure control for hiding detailsflow; interactive; palpableflowsummary*; flowglobals; name; openHTMLDetailsElement
dfnDefining instanceflow; phrasing; palpablephrasingphrasing*globalsHTMLElement
dialogDialog box or windowflowflowflowglobals; openHTMLDialogElement
divGeneric flow container, or container for name-value groups in dl elementsflow; palpableflow; dlflowglobalsHTMLDivElement
dlAssociation list consisting of zero or more name-value groupsflow; palpableflowdt*; dd*; div*; script-supporting elementsglobalsHTMLDListElement
dtLegend for corresponding dd element(s)nonedl; div*flow*globalsHTMLElement
emStress emphasisflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
embedPluginflow; phrasing; embedded; interactive; palpablephrasingemptyglobals; src; type; width; height; any*HTMLEmbedElement
fieldsetGroup of form controlsflow; listed; form-associated; palpableflowlegend*; flowglobals; disabled; form; nameHTMLFieldSetElement
figcaptionCaption for figurenonefigureflowglobalsHTMLElement
figureFigure with optional captionflow; palpableflowfigcaption*; flowglobalsHTMLElement
footerFooter for a page or sectionflow; palpableflowflow*globalsHTMLElement
formUser-submittable formflow; palpableflowflow*globals; accept-charset; action; autocomplete; enctype; method; name; novalidate; rel; targetHTMLFormElement
h1, h2, h3, h4, h5, h6Headingflow; heading; palpablelegend; summary; flowphrasingglobalsHTMLHeadingElement
headContainer for document metadatanonehtmlmetadata content*globalsHTMLHeadElement
headerIntroductory or navigational aids for a page or sectionflow; palpableflowflow*globalsHTMLElement
hgroupHeading containerflow; palpable legend; summary; flowh1; h2; h3; h4; h5; h6; script-supporting elementsglobalsHTMLElement
hrThematic breakflowflowemptyglobalsHTMLHRElement
htmlRoot elementnonenone*head*; body*globals; manifestHTMLHtmlElement
iAlternate voiceflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
iframeChild navigableflow; phrasing; embedded; interactive; palpablephrasingemptyglobals; src; srcdoc; name; sandbox; allow; allowfullscreen; width; height; referrerpolicy; loadingHTMLIFrameElement
imgImageflow; phrasing; embedded; interactive*; form-associated; palpablephrasing; pictureemptyglobals; alt; src; srcset; sizes; crossorigin; usemap; ismap; width; height; referrerpolicy; decoding; loading; fetchpriorityHTMLImageElement
inputForm controlflow; phrasing; interactive*; listed; labelable; submittable; resettable; form-associated; palpable*phrasingemptyglobals; accept; alt; autocomplete; checked; dirname; disabled; form; formaction; formenctype; formmethod; formnovalidate; formtarget; height; list; max; maxlength; min; minlength; multiple; name; pattern; placeholder; popovertarget; popovertargetaction; readonly; required; size; src; step; type; value; widthHTMLInputElement
insAn addition to the documentflow; phrasing*; palpablephrasingtransparentglobals; cite; datetimeHTMLModElement
kbdUser inputflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
labelCaption for a form controlflow; phrasing; interactive; palpablephrasingphrasing*globals; forHTMLLabelElement
legendCaption for fieldsetnonefieldsetphrasing; heading contentglobalsHTMLLegendElement
liList itemnoneol; ul; menu*flowglobals; value*HTMLLIElement
linkLink metadatametadata; flow*; phrasing*head; noscript*; phrasing*emptyglobals; href; crossorigin; rel; as; media; hreflang; type; sizes; imagesrcset; imagesizes; referrerpolicy; integrity; blocking; color; disabled; fetchpriorityHTMLLinkElement
mainContainer for the dominant contents of the documentflow; palpableflow*flowglobalsHTMLElement
mapImage mapflow; phrasing*; palpablephrasingtransparent; area*globals; nameHTMLMapElement
markHighlightflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
MathML mathMathML rootflow; phrasing; embedded; palpablephrasingper [MATHML]per [MATHML]Element
menuMenu of commandsflow; palpable*flowli; script-supporting elementsglobalsHTMLMenuElement
metaText metadatametadata; flow*; phrasing*head; noscript*; phrasing*emptyglobals; name; http-equiv; content; charset; mediaHTMLMetaElement
meterGaugeflow; phrasing; labelable; palpablephrasingphrasing*globals; value; min; max; low; high; optimumHTMLMeterElement
navSection with navigational linksflow; sectioning; palpableflowflowglobalsHTMLElement
noscriptFallback content for scriptmetadata; flow; phrasinghead*; phrasing*varies*globalsHTMLElement
objectImage, child navigable, or pluginflow; phrasing; embedded; interactive*; listed; form-associated; palpablephrasingtransparentglobals; data; type; name; form; width; heightHTMLObjectElement
olOrdered listflow; palpable*flowli; script-supporting elementsglobals; reversed; start; typeHTMLOListElement
optgroupGroup of options in a list boxnoneselectoption; script-supporting elementsglobals; disabled; labelHTMLOptGroupElement
optionOption in a list box or combo box controlnoneselect; datalist; optgrouptext*globals; disabled; label; selected; valueHTMLOptionElement
outputCalculated output valueflow; phrasing; listed; labelable; resettable; form-associated; palpablephrasingphrasingglobals; for; form; nameHTMLOutputElement
pParagraphflow; palpableflowphrasingglobalsHTMLParagraphElement
pictureImageflow; phrasing; embedded; palpablephrasingsource*; one img; script-supporting elementsglobalsHTMLPictureElement
preBlock of preformatted textflow; palpableflowphrasingglobalsHTMLPreElement
progressProgress barflow; phrasing; labelable; palpablephrasingphrasing*globals; value; maxHTMLProgressElement
qQuotationflow; phrasing; palpablephrasingphrasingglobals; citeHTMLQuoteElement
rpParenthesis for ruby annotation textnonerubytextglobalsHTMLElement
rtRuby annotation textnonerubyphrasingglobalsHTMLElement
rubyRuby annotation(s)flow; phrasing; palpablephrasingphrasing; rt; rp*globalsHTMLElement
sInaccurate textflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
sampComputer outputflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
scriptEmbedded scriptmetadata; flow; phrasing; script-supportinghead; phrasing; script-supportingscript, data, or script documentation*globals; src; type; nomodule; async; defer; crossorigin; integrity; referrerpolicy; blocking; fetchpriorityHTMLScriptElement
searchContainer for search controlsflow; palpableflowflowglobalsHTMLElement
sectionGeneric document or application sectionflow; sectioning; palpableflowflowglobalsHTMLElement
selectList box controlflow; phrasing; interactive; listed; labelable; submittable; resettable; form-associated; palpablephrasingoption; optgroup; script-supporting elementsglobals; autocomplete; disabled; form; multiple; name; required; sizeHTMLSelectElement
slotShadow tree slotflow; phrasingphrasingtransparentglobals; nameHTMLSlotElement
smallSide commentflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
sourceImage source for img or media source for video or audiononepicture; video; audioemptyglobals; type; media; src; srcset; sizes; width; heightHTMLSourceElement
spanGeneric phrasing containerflow; phrasing; palpablephrasingphrasingglobalsHTMLSpanElement
strongImportanceflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
styleEmbedded styling informationmetadatahead; noscript*text*globals; media; blockingHTMLStyleElement
subSubscriptflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
summaryCaption for detailsnonedetailsphrasing; heading contentglobalsHTMLElement
supSuperscriptflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
SVG svgSVG rootflow; phrasing; embedded; palpablephrasingper [SVG]per [SVG]SVGSVGElement
tableTableflow; palpableflowcaption*; colgroup*; thead*; tbody*; tfoot*; tr*; script-supporting elementsglobalsHTMLTableElement
tbodyGroup of rows in a tablenonetabletr; script-supporting elementsglobalsHTMLTableSectionElement
tdTable cellnonetrflowglobals; colspan; rowspan; headersHTMLTableCellElement
templateTemplatemetadata; flow; phrasing; script-supportingmetadata; phrasing; script-supporting; colgroup*emptyglobalsHTMLTemplateElement
textareaMultiline text controlsflow; phrasing; interactive; listed; labelable; submittable; resettable; form-associated; palpablephrasingtextglobals; autocomplete; cols; dirname; disabled; form; maxlength; minlength; name; placeholder; readonly; required; rows; wrapHTMLTextAreaElement
tfootGroup of footer rows in a tablenonetabletr; script-supporting elementsglobalsHTMLTableSectionElement
thTable header cellinteractive*trflow*globals; colspan; rowspan; headers; scope; abbrHTMLTableCellElement
theadGroup of heading rows in a tablenonetabletr; script-supporting elementsglobalsHTMLTableSectionElement
timeMachine-readable equivalent of date- or time-related dataflow; phrasing; palpablephrasingphrasingglobals; datetimeHTMLTimeElement
titleDocument titlemetadataheadtext*globalsHTMLTitleElement
trTable rownonetable; thead; tbody; tfootth*; td; script-supporting elementsglobalsHTMLTableRowElement
trackTimed text tracknoneaudio; videoemptyglobals; default; kind; label; src; srclangHTMLTrackElement
uUnarticulated annotationflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
ulListflow; palpable*flowli; script-supporting elementsglobalsHTMLUListElement
varVariableflow; phrasing; palpablephrasingphrasingglobalsHTMLElement
videoVideo playerflow; phrasing; embedded; interactive; palpablephrasingsource*; track*; transparent*globals; src; crossorigin; poster; preload; autoplay; playsinline; loop; muted; controls; width; heightHTMLVideoElement
wbrLine breaking opportunityflow; phrasingphrasingemptyglobalsHTMLElement
autonomous custom elementsAuthor-defined elementsflow; phrasing; palpableflow; phrasingtransparentglobals; any, as decided by the element's authorSupplied by the element's author (inherits from HTMLElement)

An asterisk (*) in a cell indicates that the actual rules are more complicated than indicated in the table above.

† Categories in the "Parents" column refer to parents that list the given categories in their content model, not to elements that themselves are in those categories. For example, the a element's "Parents" column says "phrasing", so any element whose content model contains the "phrasing" category could be a parent of an a element. Since the "flow" category includes all the "phrasing" elements, that means the th element could be a parent to an a element.

Element content categories

This section is non-normative.

List of element content categories
Category Elements Elements with exceptions
Metadata content base; link; meta; noscript; script; style; template; title
Flow content a; abbr; address; article; aside; audio; b; bdi; bdo; blockquote; br; button; canvas; cite; code; data; datalist; del; details; dfn; dialog; div; dl; em; embed; fieldset; figure; footer; form; h1; h2; h3; h4; h5; h6; header; hgroup; hr; i; iframe; img; input; ins; kbd; label; map; mark; MathML math; menu; meter; nav; noscript; object; ol; output; p; picture; pre; progress; q; ruby; s; samp; script; search; section; select; slot; small; span; strong; sub; sup; SVG svg; table; template; textarea; time; u; ul; var; video; wbr; autonomous custom elements; Text area (if it is a descendant of a map element); link (if it is allowed in the body); main (if it is a hierarchically correct main element); meta (if the itemprop attribute is present)
Sectioning content article; aside; nav; section
Heading content h1; h2; h3; h4; h5; h6; hgroup
Phrasing content a; abbr; audio; b; bdi; bdo; br; button; canvas; cite; code; data; datalist; del; dfn; em; embed; i; iframe; img; input; ins; kbd; label; map; mark; MathML math; meter; noscript; object; output; picture; progress; q; ruby; s; samp; script; select; slot; small; span; strong; sub; sup; SVG svg; template; textarea; time; u; var; video; wbr; autonomous custom elements; Text area (if it is a descendant of a map element); link (if it is allowed in the body); meta (if the itemprop attribute is present)
Embedded content audio; canvas; embed; iframe; img; MathML math; object; picture; SVG svg; video
Interactive content button; details; embed; iframe; label; select; textarea a (if the href attribute is present); audio (if the controls attribute is present); img (if the usemap attribute is present); input (if the type attribute is not in the Hidden state); video (if the controls attribute is present)
Form-associated elements button; fieldset; input; label; object; output; select; textarea; img; form-associated custom elements
Listed elements button; fieldset; input; object; output; select; textarea; form-associated custom elements
Submittable elements button; input; select; textarea; form-associated custom elements
Resettable elements input; output; select; textarea; form-associated custom elements
Autocapitalize-inheriting elements button; fieldset; input; output; select; textarea
Labelable elements button; input; meter; output; progress; select; textarea; form-associated custom elements
Palpable content a; abbr; address; article; aside; b; bdi; bdo; blockquote; button; canvas; cite; code; data; del; details; dfn; div; em; embed; fieldset; figure; footer; form; h1; h2; h3; h4; h5; h6; header; hgroup; i; iframe; img; ins; kbd; label; main; map; mark; MathML math; meter; nav; object; output; p; picture; pre; progress; q; ruby; s; samp; search; section; select; small; span; strong; sub; sup; SVG svg; table; textarea; time; u; var; video; autonomous custom elements audio (if the controls attribute is present); dl (if the element's children include at least one name-value group); input (if the type attribute is not in the Hidden state); menu (if the element's children include at least one li element); ol (if the element's children include at least one li element); ul (if the element's children include at least one li element); Text that is not inter-element whitespace
Script-supporting elements script; template

Attributes

This section is non-normative.

List of attributes (excluding event handler content attributes)
Attribute Element(s) Description Value
abbr th Alternative label to use for the header cell when referencing the cell in other contexts Text*
accept input Hint for expected file type in file upload controls Set of comma-separated tokens* consisting of valid MIME type strings with no parameters or audio/*, video/*, or image/*
accept-charset form Character encodings to use for form submission ASCII case-insensitive match for "UTF-8"
accesskey HTML elements Keyboard shortcut to activate or focus element Ordered set of unique space-separated tokens, none of which are identical to another, each consisting of one code point in length
action form URL to use for form submission Valid non-empty URL potentially surrounded by spaces
allow iframe Permissions policy to be applied to the iframe's contents Serialized permissions policy
allowfullscreen iframe Whether to allow the iframe's contents to use requestFullscreen() Boolean attribute
alt area; img; input Replacement text for use when images are not available Text*
as link Potential destination for a preload request (for rel="preload" and rel="modulepreload") Potential destination, for rel="preload"; script-like destination, for rel="modulepreload"
async script Execute script when available, without blocking while fetching Boolean attribute
autocapitalize HTML elements Recommended autocapitalization behavior (for supported input methods) "on"; "off"; "none"; "sentences"; "words"; "characters"
autocomplete form Default setting for autofill feature for controls in the form "on"; "off"
autocomplete input; select; textarea Hint for form autofill feature Autofill field name and related tokens*
autofocus HTML elements Automatically focus the element when the page is loaded Boolean attribute
autoplay audio; video Hint that the media resource can be started automatically when the page is loaded Boolean attribute
blocking link; script; style Whether the element is potentially render-blocking Unordered set of unique space-separated tokens*
charset meta Character encoding declaration "utf-8"
checked input Whether the control is checked Boolean attribute
cite blockquote; del; ins; q Link to the source of the quotation or more information about the edit Valid URL potentially surrounded by spaces
class HTML elements Classes to which the element belongs Set of space-separated tokens
color link Color to use when customizing a site's icon (for rel="mask-icon") CSS <color>
cols textarea Maximum number of characters per line Valid non-negative integer greater than zero
colspan td; th Number of columns that the cell is to span Valid non-negative integer greater than zero
content meta Value of the element Text*
contenteditable HTML elements Whether the element is editable "true"; "plaintext-only"; "false"
controls audio; video Show user agent controls Boolean attribute
coords area Coordinates for the shape to be created in an image map Valid list of floating-point numbers*
crossorigin audio; img; link; script; video How the element handles crossorigin requests "anonymous"; "use-credentials"
data object Address of the resource Valid non-empty URL potentially surrounded by spaces
datetime del; ins Date and (optionally) time of the change Valid date string with optional time
datetime time Machine-readable value Valid month string, valid date string, valid yearless date string, valid time string, valid local date and time string, valid time-zone offset string, valid global date and time string, valid week string, valid non-negative integer, or valid duration string
decoding img Decoding hint to use when processing this image for presentation "sync"; "async"; "auto"
default track Enable the track if no other text track is more suitable Boolean attribute
defer script Defer script execution Boolean attribute
dir HTML elements The text directionality of the element "ltr"; "rtl"; "auto"
dir bdo The text directionality of the element "ltr"; "rtl"
dirname input; textarea Name of form control to use for sending the element's directionality in form submission Text*
disabled button; input; optgroup; option; select; textarea; form-associated custom elements Whether the form control is disabled Boolean attribute
disabled fieldset Whether the descendant form controls, except any inside legend, are disabled Boolean attribute
disabled link Whether the link is disabled Boolean attribute
download a; area Whether to download the resource instead of navigating to it, and its filename if so Text
draggable HTML elements Whether the element is draggable "true"; "false"
enctype form Entry list encoding type to use for form submission "application/x-www-form-urlencoded"; "multipart/form-data"; "text/plain"
enterkeyhint HTML elements Hint for selecting an enter key action "enter"; "done"; "go"; "next"; "previous"; "search"; "send"
fetchpriority img; link; script Sets the priority for fetches initiated by the element "auto"; "high"; "low"
for label Associate the label with form control ID*
for output Specifies controls from which the output was calculated Unordered set of unique space-separated tokens consisting of IDs*
form button; fieldset; input; object; output; select; textarea; form-associated custom elements Associates the element with a form element ID*
formaction button; input URL to use for form submission Valid non-empty URL potentially surrounded by spaces
formenctype button; input Entry list encoding type to use for form submission "application/x-www-form-urlencoded"; "multipart/form-data"; "text/plain"
formmethod button; input Variant to use for form submission "GET"; "POST"; "dialog"
formnovalidate button; input Bypass form control validation for form submission Boolean attribute
formtarget button; input Navigable for form submission Valid navigable target name or keyword
headers td; th The header cells for this cell Unordered set of unique space-separated tokens consisting of IDs*
height canvas; embed; iframe; img; input; object; source (in picture); video Vertical dimension Valid non-negative integer
hidden HTML elements Whether the element is relevant "until-found"; "hidden"; the empty string
high meter Low limit of high range Valid floating-point number*
href a; area Address of the hyperlink Valid URL potentially surrounded by spaces
href link Address of the hyperlink Valid non-empty URL potentially surrounded by spaces
href base Document base URL Valid URL potentially surrounded by spaces
hreflang a; link Language of the linked resource Valid BCP 47 language tag
http-equiv meta Pragma directive "content-type"; "default-style"; "refresh"; "x-ua-compatible"; "content-security-policy"
id HTML elements The element's ID Text*
imagesizes link Image sizes for different page layouts (for rel="preload") Valid source size list
imagesrcset link Images to use in different situations, e.g., high-resolution displays, small monitors, etc. (for rel="preload") Comma-separated list of image candidate strings
inert HTML elements Whether the element is inert. Boolean attribute
inputmode HTML elements Hint for selecting an input modality "none"; "text"; "tel"; "email"; "url"; "numeric"; "decimal"; "search"
integrity link; script Integrity metadata used in Subresource Integrity checks [SRI] Text
is HTML elements Creates a customized built-in element Valid custom element name of a defined customized built-in element
ismap img Whether the image is a server-side image map Boolean attribute
itemid HTML elements Global identifier for a microdata item Valid URL potentially surrounded by spaces
itemprop HTML elements Property names of a microdata item Unordered set of unique space-separated tokens consisting of valid absolute URLs, defined property names, or text*
itemref HTML elements Referenced elements Unordered set of unique space-separated tokens consisting of IDs*
itemscope HTML elements Introduces a microdata item Boolean attribute
itemtype HTML elements Item types of a microdata item Unordered set of unique space-separated tokens consisting of valid absolute URLs*
kind track The type of text track "subtitles"; "captions"; "descriptions"; "chapters"; "metadata"
label optgroup; option; track User-visible label Text
lang HTML elements Language of the element Valid BCP 47 language tag or the empty string
list input List of autocomplete options ID*
loading iframe; img Used when determining loading deferral "lazy"; "eager"
loop audio; video Whether to loop the media resource Boolean attribute
low meter High limit of low range Valid floating-point number*
max input Maximum value Varies*
max meter; progress Upper bound of range Valid floating-point number*
maxlength input; textarea Maximum length of value Valid non-negative integer
media link; meta; source; style Applicable media Valid media query list
method form Variant to use for form submission "GET"; "POST"; "dialog"
min input Minimum value Varies*
min meter Lower bound of range Valid floating-point number*
minlength input; textarea Minimum length of value Valid non-negative integer
multiple input; select Whether to allow multiple values Boolean attribute
muted audio; video Whether to mute the media resource by default Boolean attribute
name button; fieldset; input; output; select; textarea; form-associated custom elements Name of the element to use for form submission and in the form.elements API Text*
name details Name of group of mutually-exclusive details elements Text*
name form Name of form to use in the document.forms API Text*
name iframe; object Name of content navigable Valid navigable target name or keyword
name map Name of image map to reference from the usemap attribute Text*
name meta Metadata name Text*
name slot Name of shadow tree slot Text
nomodule script Prevents execution in user agents that support module scripts Boolean attribute
nonce HTML elements Cryptographic nonce used in Content Security Policy checks [CSP] Text
novalidate form Bypass form control validation for form submission Boolean attribute
open details Whether the details are visible Boolean attribute
open dialog Whether the dialog box is showing Boolean attribute
optimum meter Optimum value in gauge Valid floating-point number*
pattern input Pattern to be matched by the form control's value Regular expression matching the JavaScript Pattern production
ping a; area URLs to ping Set of space-separated tokens consisting of valid non-empty URLs
placeholder input; textarea User-visible label to be placed within the form control Text*
playsinline video Encourage the user agent to display video content within the element's playback area Boolean attribute
popover HTML elements Makes the element a popover element "auto"; "manual";
popovertarget input; button Targets a popover element to toggle, show, or hide ID*
popovertargetaction input; button Indicates whether a targeted popover element is to be toggled, shown, or hidden "toggle"; "show"; "hide"
poster video Poster frame to show prior to video playback Valid non-empty URL potentially surrounded by spaces
preload audio; video Hints how much buffering the media resource will likely need "none"; "metadata"; "auto"
readonly input; textarea Whether to allow the value to be edited by the user Boolean attribute
readonly form-associated custom elements Affects willValidate, plus any behavior added by the custom element author Boolean attribute
referrerpolicy a; area; iframe; img; link; script Referrer policy for fetches initiated by the element Referrer policy
rel a; area Relationship between the location in the document containing the hyperlink and the destination resource Unordered set of unique space-separated tokens*
rel link Relationship between the document containing the hyperlink and the destination resource Unordered set of unique space-separated tokens*
required input; select; textarea Whether the control is required for form submission Boolean attribute
reversed ol Number the list backwards Boolean attribute
rows textarea Number of lines to show Valid non-negative integer greater than zero
rowspan td; th Number of rows that the cell is to span Valid non-negative integer
sandbox iframe Security rules for nested content Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of
scope th Specifies which cells the header cell applies to "row"; "col"; "rowgroup"; "colgroup"
selected option Whether the option is selected by default Boolean attribute
shadowrootmode template Enables streaming declarative shadow roots "open"; "closed"
shadowrootdelegatesfocus template Sets delegates focus on a declarative shadow root Boolean attribute
shadowrootclonable template Sets clonable on a declarative shadow root Boolean attribute
shape area The kind of shape to be created in an image map "circle"; "default"; "poly"; "rect"
size input; select Size of the control Valid non-negative integer greater than zero
sizes link Sizes of the icons (for rel="icon") Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of sizes*
sizes img; source Image sizes for different page layouts Valid source size list
slot HTML elements The element's desired slot Text
span col; colgroup Number of columns spanned by the element Valid non-negative integer greater than zero
spellcheck HTML elements Whether the element is to have its spelling and grammar checked "true"; "false"; the empty string
src audio; embed; iframe; img; input; script; source (in video or audio); track; video Address of the resource Valid non-empty URL potentially surrounded by spaces
srcdoc iframe A document to render in the iframe The source of an iframe srcdoc document*
srclang track Language of the text track Valid BCP 47 language tag
srcset img; source Images to use in different situations, e.g., high-resolution displays, small monitors, etc. Comma-separated list of image candidate strings
start ol Starting value of the list Valid integer
step input Granularity to be matched by the form control's value Valid floating-point number greater than zero, or "any"
style HTML elements Presentational and formatting instructions CSS declarations*
tabindex HTML elements Whether the element is focusable and sequentially focusable, and the relative order of the element for the purposes of sequential focus navigation Valid integer
target a; area Navigable for hyperlink navigation Valid navigable target name or keyword
target base Default navigable for hyperlink navigation and form submission Valid navigable target name or keyword
target form Navigable for form submission Valid navigable target name or keyword
title HTML elements Advisory information for the element Text
title abbr; dfn Full term or expansion of abbreviation Text
title input Description of pattern (when used with pattern attribute) Text
title link Title of the link Text
title link; style CSS style sheet set name Text
translate HTML elements Whether the element is to be translated when the page is localized "yes"; "no"
type a; link Hint for the type of the referenced resource Valid MIME type string
type button Type of button "submit"; "reset"; "button"
type embed; object; source Type of embedded resource Valid MIME type string
type input Type of form control input type keyword
type ol Kind of list marker "1"; "a"; "A"; "i"; "I"
type script Type of script "module"; a valid MIME type string that is not a JavaScript MIME type essence match
usemap img Name of image map to use Valid hash-name reference*
value button; option Value to be used for form submission Text
value data Machine-readable value Text*
value input Value of the form control Varies*
value li Ordinal value of the list item Valid integer
value meter; progress Current value of the element Valid floating-point number
width canvas; embed; iframe; img; input; object; source (in picture); video Horizontal dimension Valid non-negative integer
wrap textarea How the value of the form control is to be wrapped for form submission "soft"; "hard"
writingsuggestions HTML elements Whether the element can offer writing suggestions or not. "true"; "false"; the empty string

An asterisk (*) in a cell indicates that the actual rules are more complicated than indicated in the table above.


HTMLElement/drag_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/dragend_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/dragenter_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/dragleave_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/dragover_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/dragstart_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+

HTMLElement/drop_event

Support in all current engines.

Firefox9+Safari3.1+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12+
List of event handler content attributes
Attribute Element(s) Description Value
onauxclick HTML elements auxclick event handler Event handler content attribute
onafterprint body afterprint event handler for Window object Event handler content attribute
onbeforematch HTML elements beforematch event handler Event handler content attribute
onbeforeprint body beforeprint event handler for Window object Event handler content attribute
onbeforeunload body beforeunload event handler for Window object Event handler content attribute
onbeforetoggle HTML elements beforetoggle event handler Event handler content attribute
onblur HTML elements blur event handler Event handler content attribute
oncancel HTML elements cancel event handler Event handler content attribute
oncanplay HTML elements canplay event handler Event handler content attribute
oncanplaythrough HTML elements canplaythrough event handler Event handler content attribute
onchange HTML elements change event handler Event handler content attribute
onclick HTML elements click event handler Event handler content attribute
onclose HTML elements close event handler Event handler content attribute
oncontextlost HTML elements contextlost event handler Event handler content attribute
oncontextmenu HTML elements contextmenu event handler Event handler content attribute
oncontextrestored HTML elements contextrestored event handler Event handler content attribute
oncopy HTML elements copy event handler Event handler content attribute
oncuechange HTML elements cuechange event handler Event handler content attribute
oncut HTML elements cut event handler Event handler content attribute
ondblclick HTML elements dblclick event handler Event handler content attribute
ondrag HTML elements drag event handler Event handler content attribute
ondragend HTML elements dragend event handler Event handler content attribute
ondragenter HTML elements dragenter event handler Event handler content attribute
ondragleave HTML elements dragleave event handler Event handler content attribute
ondragover HTML elements dragover event handler Event handler content attribute
ondragstart HTML elements dragstart event handler Event handler content attribute
ondrop HTML elements drop event handler Event handler content attribute
ondurationchange HTML elements durationchange event handler Event handler content attribute
onemptied HTML elements emptied event handler Event handler content attribute
onended HTML elements ended event handler Event handler content attribute
onerror HTML elements error event handler Event handler content attribute
onfocus HTML elements focus event handler Event handler content attribute
onformdata HTML elements formdata event handler Event handler content attribute
onhashchange body hashchange event handler for Window object Event handler content attribute
oninput HTML elements input event handler Event handler content attribute
oninvalid HTML elements invalid event handler Event handler content attribute
onkeydown HTML elements keydown event handler Event handler content attribute
onkeypress HTML elements keypress event handler Event handler content attribute
onkeyup HTML elements keyup event handler Event handler content attribute
onlanguagechange body languagechange event handler for Window object Event handler content attribute
onload HTML elements load event handler Event handler content attribute
onloadeddata HTML elements loadeddata event handler Event handler content attribute
onloadedmetadata HTML elements loadedmetadata event handler Event handler content attribute
onloadstart HTML elements loadstart event handler Event handler content attribute
onmessage body message event handler for Window object Event handler content attribute
onmessageerror body messageerror event handler for Window object Event handler content attribute
onmousedown HTML elements mousedown event handler Event handler content attribute
onmouseenter HTML elements mouseenter event handler Event handler content attribute
onmouseleave HTML elements mouseleave event handler Event handler content attribute
onmousemove HTML elements mousemove event handler Event handler content attribute
onmouseout HTML elements mouseout event handler Event handler content attribute
onmouseover HTML elements mouseover event handler Event handler content attribute
onmouseup HTML elements mouseup event handler Event handler content attribute
onoffline body offline event handler for Window object Event handler content attribute
ononline body online event handler for Window object Event handler content attribute
onpageswap body pageswap event handler for Window object Event handler content attribute
onpagehide body pagehide event handler for Window object Event handler content attribute
onpagereveal body pagereveal event handler for Window object Event handler content attribute
onpageshow body pageshow event handler for Window object Event handler content attribute
onpaste HTML elements paste event handler Event handler content attribute
onpause HTML elements pause event handler Event handler content attribute
onplay HTML elements play event handler Event handler content attribute
onplaying HTML elements playing event handler Event handler content attribute
onpopstate body popstate event handler for Window object Event handler content attribute
onprogress HTML elements progress event handler Event handler content attribute
onratechange HTML elements ratechange event handler Event handler content attribute
onreset HTML elements reset event handler Event handler content attribute
onresize HTML elements resize event handler Event handler content attribute
onrejectionhandled body rejectionhandled event handler for Window object Event handler content attribute
onscroll HTML elements scroll event handler Event handler content attribute
onscrollend HTML elements scrollend event handler Event handler content attribute
onsecuritypolicyviolation HTML elements securitypolicyviolation event handler Event handler content attribute
onseeked HTML elements seeked event handler Event handler content attribute
onseeking HTML elements seeking event handler Event handler content attribute
onselect HTML elements select event handler Event handler content attribute
onslotchange HTML elements slotchange event handler Event handler content attribute
onstalled HTML elements stalled event handler Event handler content attribute
onstorage body storage event handler for Window object Event handler content attribute
onsubmit HTML elements submit event handler Event handler content attribute
onsuspend HTML elements suspend event handler Event handler content attribute
ontimeupdate HTML elements timeupdate event handler Event handler content attribute
ontoggle HTML elements toggle event handler Event handler content attribute
onunhandledrejection body unhandledrejection event handler for Window object Event handler content attribute
onunload body unload event handler for Window object Event handler content attribute
onvolumechange HTML elements volumechange event handler Event handler content attribute
onwaiting HTML elements waiting event handler Event handler content attribute
onwheel HTML elements wheel event handler Event handler content attribute

Element interfaces

This section is non-normative.

List of interfaces for elements
Element(s) Interface(s)
a HTMLAnchorElement : HTMLElement
abbr HTMLElement
address HTMLElement
area HTMLAreaElement : HTMLElement
article HTMLElement
aside HTMLElement
audio HTMLAudioElement : HTMLMediaElement : HTMLElement
b HTMLElement
base HTMLBaseElement : HTMLElement
bdi HTMLElement
bdo HTMLElement
blockquote HTMLQuoteElement : HTMLElement
body HTMLBodyElement : HTMLElement
br HTMLBRElement : HTMLElement
button HTMLButtonElement : HTMLElement
canvas HTMLCanvasElement : HTMLElement
caption HTMLTableCaptionElement : HTMLElement
cite HTMLElement
code HTMLElement
col HTMLTableColElement : HTMLElement
colgroup HTMLTableColElement : HTMLElement
data HTMLDataElement : HTMLElement
datalist HTMLDataListElement : HTMLElement
dd HTMLElement
del HTMLModElement : HTMLElement
details HTMLDetailsElement : HTMLElement
dfn HTMLElement
dialog HTMLDialogElement : HTMLElement
div HTMLDivElement : HTMLElement
dl HTMLDListElement : HTMLElement
dt HTMLElement
em HTMLElement
embed HTMLEmbedElement : HTMLElement
fieldset HTMLFieldSetElement : HTMLElement
figcaption HTMLElement
figure HTMLElement
footer HTMLElement
form HTMLFormElement : HTMLElement
h1 HTMLHeadingElement : HTMLElement
h2 HTMLHeadingElement : HTMLElement
h3 HTMLHeadingElement : HTMLElement
h4 HTMLHeadingElement : HTMLElement
h5 HTMLHeadingElement : HTMLElement
h6 HTMLHeadingElement : HTMLElement
head HTMLHeadElement : HTMLElement
header HTMLElement
hgroup HTMLElement
hr HTMLHRElement : HTMLElement
html HTMLHtmlElement : HTMLElement
i HTMLElement
iframe HTMLIFrameElement : HTMLElement
img HTMLImageElement : HTMLElement
input HTMLInputElement : HTMLElement
ins HTMLModElement : HTMLElement
kbd HTMLElement
label HTMLLabelElement : HTMLElement
legend HTMLLegendElement : HTMLElement
li HTMLLIElement : HTMLElement
link HTMLLinkElement : HTMLElement
main HTMLElement
map HTMLMapElement : HTMLElement
mark HTMLElement
menu HTMLMenuElement : HTMLElement
meta HTMLMetaElement : HTMLElement
meter HTMLMeterElement : HTMLElement
nav HTMLElement
noscript HTMLElement
object HTMLObjectElement : HTMLElement
ol HTMLOListElement : HTMLElement
optgroup HTMLOptGroupElement : HTMLElement
option HTMLOptionElement : HTMLElement
output HTMLOutputElement : HTMLElement
p HTMLParagraphElement : HTMLElement
picture HTMLPictureElement : HTMLElement
pre HTMLPreElement : HTMLElement
progress HTMLProgressElement : HTMLElement
q HTMLQuoteElement : HTMLElement
rp HTMLElement
rt HTMLElement
ruby HTMLElement
s HTMLElement
samp HTMLElement
search HTMLElement
script HTMLScriptElement : HTMLElement
section HTMLElement
select HTMLSelectElement : HTMLElement
slot HTMLSlotElement : HTMLElement
small HTMLElement
source HTMLSourceElement : HTMLElement
span HTMLSpanElement : HTMLElement
strong HTMLElement
style HTMLStyleElement : HTMLElement
sub HTMLElement
summary HTMLElement
sup HTMLElement
table HTMLTableElement : HTMLElement
tbody HTMLTableSectionElement : HTMLElement
td HTMLTableCellElement : HTMLElement
template HTMLTemplateElement : HTMLElement
textarea HTMLTextAreaElement : HTMLElement
tfoot HTMLTableSectionElement : HTMLElement
th HTMLTableCellElement : HTMLElement
thead HTMLTableSectionElement : HTMLElement
time HTMLTimeElement : HTMLElement
title HTMLTitleElement : HTMLElement
tr HTMLTableRowElement : HTMLElement
track HTMLTrackElement : HTMLElement
u HTMLElement
ul HTMLUListElement : HTMLElement
var HTMLElement
video HTMLVideoElement : HTMLMediaElement : HTMLElement
wbr HTMLElement
custom elements supplied by the element's author (inherits from HTMLElement)

All interfaces

This section is non-normative.

Events

This section is non-normative.

The following table lists events fired by this document, excluding those already defined in media element events and drag-and-drop events.

List of events
Event Interface Interesting targets Description
DOMContentLoaded

Window/DOMContentLoaded_event

Support in all current engines.

Firefox1+Safari3.1+Chrome1+
Opera9+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android10.1+
Event Document Fired at the Document once the parser has finished
afterprint

Window/afterprint_event

Support in all current engines.

Firefox6+Safari13+Chrome63+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event Window Fired at the Window after printing
beforeprint

Window/beforeprint_event

Support in all current engines.

Firefox6+Safari13+Chrome63+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event Window Fired at the Window before printing
beforematch

Element/beforematch_event

Support in one engine only.

FirefoxNoSafariNoChrome102+
OperaNoEdge102+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event Elements Fired on elements with the hidden=until-found attribute before they are revealed.
beforetoggle

HTMLElement/beforetoggle_event

Support in all current engines.

Firefox🔰 114+Safaripreview+Chrome114+
Opera?Edge114+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
ToggleEvent Elements Fired on elements with the popover attribute when they are transitioning between showing and hidden
beforeunload

Window/beforeunload_event

Support in all current engines.

Firefox1+Safari3+Chrome1+
Opera12+Edge79+
Edge (Legacy)12+Internet Explorer4+
Firefox Android?Safari iOS1+Chrome Android?WebView Android?Samsung Internet?Opera Android12+
BeforeUnloadEvent Window Fired at the Window when the page is about to be unloaded, in case the page would like to show a warning prompt
blur Event Window, elements Fired at nodes when they stop being focused
cancel

HTMLDialogElement/cancel_event

Support in all current engines.

Firefox98+Safari15.4+Chrome37+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome AndroidNoWebView Android?Samsung Internet?Opera Android?
Event CloseWatcher, dialog elements, input elements Fired at CloseWatcher objects or dialog elements when they receive a close request, or at input elements in the File state when the user does not change their selection
change

HTMLElement/change_event

Support in all current engines.

Firefox1+Safari3+Chrome1+
Opera9+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android10.1+
Event Form controls Fired at controls when the user commits a value change (see also the input event)
click PointerEvent Elements Normally a mouse event; also synthetically fired at an element before its activation behavior is run, when an element is activated from a non-pointer input device (e.g. a keyboard)
close

HTMLDialogElement/close_event

Support in all current engines.

Firefox98+Safari15.4+Chrome37+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event CloseWatcher, dialog elements, MessagePort Fired at CloseWatcher objects or dialog elements when they are closed via a close request or via web developer code, or at MessagePort objects when disentangled
connect

SharedWorkerGlobalScope/connect_event

Support in all current engines.

Firefox29+Safari16+Chrome4+
Opera10.6+Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS16+Chrome Android?WebView Android37+Samsung Internet?Opera Android11+
MessageEvent SharedWorkerGlobalScope Fired at a shared worker's global scope when a new client connects
contextlost

HTMLCanvasElement/webglcontextlost_event

Support in one engine only.

FirefoxNoSafariNoChrome98+
Opera?Edge98+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event canvas elements, OffscreenCanvas objects Fired when the corresponding CanvasRenderingContext2D or OffscreenCanvasRenderingContext2D is lost
contextrestored

HTMLCanvasElement/contextrestored_event

Support in one engine only.

FirefoxNoSafariNoChrome98+
Opera?Edge98+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
Event canvas elements, OffscreenCanvas objects Fired when the corresponding CanvasRenderingContext2D or OffscreenCanvasRenderingContext2D is restored after being lost
currententrychange NavigationCurrentEntryChangeEvent Navigation Fired when navigation.currentEntry changes
dispose Event NavigationHistoryEntry Fired when the session history entry corresponding to the NavigationHistoryEntry has been permanently evicted from session history and can no longer be traversed to
error

EventSource/error_event

Support in all current engines.

Firefox6+Safari5+Chrome6+
Opera12+Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android45+Safari iOS5+Chrome Android?WebView Android?Samsung Internet?Opera Android12+

Window/error_event

Support in all current engines.

Firefox6+Safari5.1+Chrome10+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android?
Event or ErrorEvent Global scope objects, Worker objects, elements, networking-related objects Fired when unexpected errors occur (e.g. networking errors, script errors, decoding errors)
focus Event Window, elements Fired at nodes gaining focus
formdata

HTMLFormElement/formdata_event

Support in all current engines.

Firefox72+Safari15+Chrome77+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
FormDataEvent form elements Fired at a form element when it is constructing the entry list
hashchange

Window/hashchange_event

Support in all current engines.

Firefox3.6+Safari5+Chrome8+
Opera10.6+Edge79+
Edge (Legacy)12+Internet Explorer8+
Firefox Android?Safari iOS5+Chrome Android?WebView Android37+Samsung Internet?Opera Android11+
HashChangeEvent Window Fired at the Window when the fragment part of the document's URL changes
input Event Elements Fired when the user changes the contenteditable element's content, or the form control's value. See also the change event for form controls.
invalid

HTMLInputElement/invalid_event

Support in all current engines.

Firefox4+Safari5+Chrome10+
Opera10+Edge79+
Edge (Legacy)12+Internet Explorer10+
Firefox Android64+Safari iOS5+Chrome Android?WebView Android4+Samsung Internet4.0+Opera Android12+
Event Form controls Fired at controls during form validation if they do not satisfy their constraints
languagechange

Window/languagechange_event

Support in all current engines.

Firefox32+Safari10.1+Chrome37+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android4+Safari iOS?Chrome Android?WebView Android?Samsung Internet4.0+Opera Android?

WorkerGlobalScope/languagechange_event

Support in all current engines.

Firefox74+Safari4+Chrome4+
Opera11.5+Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS5+Chrome Android?WebView Android37+Samsung Internet?Opera Android?
Event Global scope objects Fired at the global scope object when the user's preferred languages change
load Event Window, elements Fired at the Window when the document has finished loading; fired at an element containing a resource (e.g. img, embed) when its resource has finished loading
message

BroadcastChannel/message_event

Support in all current engines.

Firefox38+Safari15.4+Chrome54+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?

DedicatedWorkerGlobalScope/message_event

Support in all current engines.

Firefox3.5+Safari4+Chrome4+
Opera10.6+Edge79+
Edge (Legacy)12+Internet Explorer10+
Firefox Android?Safari iOS5+Chrome Android?WebView Android37+Samsung Internet?Opera Android11.5+

EventSource/message_event

Support in all current engines.

Firefox6+Safari5+Chrome6+
Opera12+Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android45+Safari iOS5+Chrome Android?WebView Android?Samsung Internet?Opera Android12+

MessagePort/message_event

Support in all current engines.

Firefox41+Safari5+Chrome2+
Opera10.6+Edge79+
Edge (Legacy)12+Internet Explorer10+
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android11.5+

Window/message_event

Support in all current engines.

Firefox9+Safari4+Chrome60+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer8+
Firefox Android?Safari iOS4+Chrome Android?WebView Android?Samsung Internet?Opera Android47+

Worker/message_event

Support in all current engines.

Firefox3.5+Safari4+Chrome4+
Opera10.6+Edge79+
Edge (Legacy)12+Internet Explorer10+
Firefox Android?Safari iOS5+Chrome Android?WebView Android?Samsung Internet?Opera Android11.5+
MessageEvent Window, EventSource, MessagePort, BroadcastChannel, DedicatedWorkerGlobalScope, Worker, ServiceWorkerContainer Fired at an object when it receives a message
messageerror

BroadcastChannel/messageerror_event

Support in all current engines.

Firefox57+Safari15.4+Chrome60+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android47+

DedicatedWorkerGlobalScope/messageerror_event

Support in all current engines.

Firefox57+Safari16.4+Chrome60+
Opera?Edge79+
Edge (Legacy)18Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android47+

MessagePort/messageerror_event

Support in all current engines.

Firefox57+Safari16.4+Chrome60+
Opera?Edge79+
Edge (Legacy)18Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android47+

Window/messageerror_event

Support in all current engines.

Firefox57+Safari16.4+Chrome60+
Opera?Edge79+
Edge (Legacy)18Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android47+

Worker/messageerror_event

Support in all current engines.

Firefox57+Safari16.4+Chrome60+
Opera?Edge79+
Edge (Legacy)18Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android47+
MessageEvent Window, MessagePort, BroadcastChannel, DedicatedWorkerGlobalScope, Worker, ServiceWorkerContainer Fired at an object when it receives a message that cannot be deserialized
navigate NavigateEvent Navigation Fired before the navigable navigates, reloads, traverses, or otherwise changes its URL
navigateerror ErrorEvent Navigation Fired when a navigation does not complete successfully
navigatesuccess Event Navigation Fired when a navigation completes successfully
offline

Window/offline_event

Support in all current engines.

Firefox9+Safari4+Chrome3+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS3+Chrome Android?WebView Android37+Samsung Internet?Opera Android?
Event Global scope objects Fired at the global scope object when the network connections fails
online

Window/online_event

Support in all current engines.

Firefox9+Safari4+Chrome3+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS3+Chrome Android?WebView Android37+Samsung Internet?Opera Android?
Event Global scope objects Fired at the global scope object when the network connections returns
open

EventSource/open_event

Support in all current engines.

Firefox6+Safari5+Chrome6+
Opera12+Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android45+Safari iOS5+Chrome Android?WebView Android?Samsung Internet?Opera Android12+
Event EventSource Fired at EventSource objects when a connection is established
pageswap PageSwapEvent Window Fired at the Window right before a document is unloaded as a result of a navigation.
pagehide

Window/pagehide_event

Support in all current engines.

Firefox6+Safari5+Chrome3+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer11
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android?
PageTransitionEvent Window Fired at the Window when the page's session history entry stops being the active entry
pagereveal PageRevealEvent Window Fired at the Window when the page begins to render for the first time after it has been initialized or reactivated
pageshow

Window/pageshow_event

Support in all current engines.

Firefox6+Safari5+Chrome3+
Opera?Edge79+
Edge (Legacy)12+Internet Explorer11
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android?
PageTransitionEvent Window Fired at the Window when the page's session history entry becomes the active entry
pointercancel PointerEvent Elements and Text nodes Fired at the source node when the user attempts to initiate a drag-and-drop operation
popstate

Window/popstate_event

Support in all current engines.

Firefox4+Safari5+Chrome5+
Opera11.5+Edge79+
Edge (Legacy)12+Internet Explorer10+
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android11.5+
PopStateEvent Window Fired at the Window when in some cases of session history traversal
readystatechange

Document/readystatechange_event

Support in all current engines.

Firefox4+Safari5.1+Chrome9+
Opera12.1+Edge79+
Edge (Legacy)12+Internet Explorer4+
Firefox Android?Safari iOS?Chrome Android?WebView Android37+Samsung Internet?Opera Android12.1+
Event Document Fired at the Document when it finishes parsing and again when all its subresources have finished loading
rejectionhandled PromiseRejectionEvent Global scope objects Fired at global scope objects when a previously-unhandled promise rejection becomes handled
reset

HTMLFormElement/reset_event

Support in all current engines.

Firefox6+Safari3+Chrome1+
Opera12.1+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS1+Chrome Android?WebView Android37+Samsung Internet?Opera Android12.1+
Event form elements Fired at a form element when it is reset
select

HTMLInputElement/select_event

Support in all current engines.

Firefox6+Safari1+Chrome1+
Opera12.1+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12.1+

HTMLTextAreaElement/select_event

Support in all current engines.

Firefox6+Safari1+Chrome1+
Opera12.1+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android12.1+
Event Form controls Fired at form controls when their text selection is adjusted (whether by an API or by the user)
storage

Window/storage_event

Support in all current engines.

Firefox45+Safari4+Chrome1+
Opera?Edge79+
Edge (Legacy)15+Internet Explorer9+
Firefox Android?Safari iOS4+Chrome Android?WebView Android37+Samsung Internet?Opera Android?
StorageEvent Window Fired at Window event when the corresponding localStorage or sessionStorage storage areas change
submit

HTMLFormElement/submit_event

Support in all current engines.

Firefox1+Safari3+Chrome1+
Opera8+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS1+Chrome Android?WebView Android?Samsung Internet?Opera Android10.1+
SubmitEvent form elements Fired at a form element when it is submitted
toggle

HTMLDetailsElement/toggle_event

Support in all current engines.

Firefox49+Safari10.1+Chrome36+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?

HTMLElement/toggle_event

Support in all current engines.

Firefox🔰 114+Safaripreview+Chrome114+
Opera?Edge114+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?
ToggleEvent details and popover elements Fired at details elements when they open or close; fired on elements with the popover attribute when they are transitioning between showing and hidden
unhandledrejection

Window/unhandledrejection_event

Support in all current engines.

Firefox69+Safari11+Chrome49+
Opera?Edge79+
Edge (Legacy)?Internet ExplorerNo
Firefox Android?Safari iOS11.3+Chrome Android?WebView Android?Samsung Internet?Opera Android?
PromiseRejectionEvent Global scope objects Fired at global scope objects when a promise rejection goes unhandled
unload

Window/unload_event

Support in all current engines.

Firefox1+Safari3+Chrome1+
Opera4+Edge79+
Edge (Legacy)12+Internet Explorer4+
Firefox Android?Safari iOS1+Chrome Android?WebView Android?Samsung Internet?Opera Android10.1+
Event Window Fired at the Window object when the page is going away
visibilitychange

Document/visibilitychange_event

Support in all current engines.

Firefox56+Safari14.1+Chrome62+
Opera49+Edge79+
Edge (Legacy)18Internet Explorer🔰 10+
Firefox Android?Safari iOS?Chrome Android?WebView Android62+Samsung Internet?Opera Android46+
Event Document Fired at the Document object when the page becomes visible or hidden to the user

HTTP headers

This section is non-normative.

The following HTTP request headers are defined by this specification:

The following HTTP response headers are defined by this specification:

MIME types

This section is non-normative.

The following MIME types are mentioned in this specification:

application/atom+xml
Atom [ATOM]
application/json
JSON [JSON]
application/octet-stream
Generic binary data [RFC2046]
application/microdata+json
Microdata as JSON
application/rss+xml
RSS
application/x-www-form-urlencoded
Form submission
application/xhtml+xml
HTML
application/xml
XML [XML] [RFC7303]
image/gif
GIF images [GIF]
image/jpeg
JPEG images [JPEG]
image/png
PNG images [PNG]
image/svg+xml
SVG images [SVG]
multipart/form-data
Form submission [RFC7578]
multipart/mixed
Generic mixed content [RFC2046]
multipart/x-mixed-replace
Streaming server push
text/css
CSS [CSS]
text/event-stream
Server-sent event streams
text/javascript
JavaScript [JAVASCRIPT] [RFC9239]
text/json
JSON (legacy type)
text/plain
Generic plain text [RFC2046] [RFC3676]
text/html
HTML
text/ping
Hyperlink auditing
text/uri-list
List of URLs [RFC2483]
text/vcard
vCard [RFC6350]
text/vtt
WebVTT [WEBVTT]
text/xml
XML [XML] [RFC7303]
video/mp4
MPEG-4 video [RFC4337]
video/mpeg
MPEG video [RFC2046]